U.S. patent number 4,600,344 [Application Number 06/558,397] was granted by the patent office on 1986-07-15 for push-on plastic wing-nut fastener.
This patent grant is currently assigned to Illinois Tool Works Inc.. Invention is credited to Richard F. Daubert, Brian R. Peek, Paul M. Sutenbach.
United States Patent |
4,600,344 |
Sutenbach , et al. |
July 15, 1986 |
Push-on plastic wing-nut fastener
Abstract
A one-piece plastic wing-nut fastener is constructed to push
onto a threaded stud and be held in threaded engagement therewith
through the use of a pair of opposing arcuate thin wall sections
which are formed with internal threads and which flex radially
outward whenever the fastener is pushed onto a threaded stud to
provide a ratcheting action therebetween. The thin wall sections
are supported on a base member by a U-shaped support having a head
section and a pair of leg portions. The pair of leg portions are
integrally formed with the base portion and extend between the base
portion and head portion in a parallel relationship with the thin
wall sections. The pair of thin wall sections are integrally formed
between the base and the head portion with its axis in alignment
with an enlarged aperture in the base portion and an enlarged
central opening in the head portion.
Inventors: |
Sutenbach; Paul M. (Chicago,
IL), Peek; Brian R. (Steger, IL), Daubert; Richard F.
(Tinley Park, IL) |
Assignee: |
Illinois Tool Works Inc.
(Chicago, IL)
|
Family
ID: |
24229384 |
Appl.
No.: |
06/558,397 |
Filed: |
December 5, 1983 |
Current U.S.
Class: |
411/435; 411/437;
411/510; 411/512; 411/907; 411/908 |
Current CPC
Class: |
F16B
37/0842 (20130101); Y10S 411/908 (20130101); Y10S
411/907 (20130101); F16B 37/16 (20130101) |
Current International
Class: |
F16B
37/08 (20060101); F16B 37/16 (20060101); F16B
37/00 (20060101); F16B 037/16 () |
Field of
Search: |
;411/435,508-510,512,437,908,416,423,418,409,182,429,431,433,436,904,907,913
;10/86W |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Smith; Gary L.
Assistant Examiner: Gall; Lloyd A.
Attorney, Agent or Firm: O'Brien; J. P. Buckman; T. W.
Claims
We claim:
1. A wing-nut fastener of the type that can be pushed onto a
threaded stud and be held in threaded engagement and that is molded
into a plastic one-piece structure comprising a base having a
central aperture, a U-shaped support having a head portion and a
pair of leg portions, said head portion having a central opening in
axial alignment with said central aperture, said central aperture
and said central opening having a diameter slightly larger than the
cross dimension of a particular thread pitch, said leg portions
integrally formed with said base, and a pair of thread forming
members extending between said base and said head portion, each of
said thread forming members having the opposite ends integrally
formed with said base and said head portion and having the length
of each thread forming member between said opposite ends free to
flex, each of said thread forming members having an arcuate thin
wall section with internal thread surfaces which together form a
plurality of screw threads matching said particular thread pitch in
axial alignment with said central opening and said central
aperture, where the thickness of said thin wall sections of said
thread forming members is selected to permit said thin wall
sections to flex radially outward a sufficient amount to permit
said plurality of screw threads to ratchet over the threads of a
threaded stud having said particular thread pitch when said
fastener is pushed inwardly thereon.
2. A wing-nut fastener as defined in claim 1, wherein the flank of
each of said thread surfaces of said thin wall sections which faces
towards said base has a convex curvature to ease the ratcheting of
said plurality of screw threads over the threads of a threaded stud
having said particular thread pitch when said fastener is pushed
inwardly thereon.
3. A wing-nut fastener as defined in claim 1, wherein the axial
distance between said central opening and said central aperture is
less than the length of a particular threaded stud such that the
free end on said particular threaded stud will be contained in said
central opening of said head portion when said fastener is fully
seated onto said particular threaded stud to thereby rigidly
support said fastener thereon.
4. A wing-nut fastener as defined in claim 1, wherein each of said
leg portions taper inwardly from said base towards said head
portion in a perpendicular direction relative to the longitudinal
dimension of said head portion to thereby reinforce said head
portion and said pair of thread forming members.
5. A wing-nut fastener of the type that can be pushed onto a
threaded stud and be held in threaded engagement and that is molded
into a one-piece plastic structure, comprising a disc-shaped base
having a central aperture, a U-shaped support having a head portion
and a pair of leg portions, said head portion having a
collar-shaped center section with a cylindrical opening in axial
alignment with said central aperture, said cylindrical opening and
said central aperture having a diameter slightly larger than the
cross dimension of a particular thread pitch, said leg portions
being integrally formed in a perpendicular relation with said base,
and a pair of thread forming members extending between said base
and said head portion, each of said thread forming members having
the opposite ends integrally formed with said base and said head
portion and having the length of each thread forming member between
said opposite ends free to flex, each of said thread forming
members having an arcuate thin wall section with internal thread
surfaces which together form a plurality of screw threads matching
said particular thread pitch in axial alignment with said central
aperture and said cylindrical opening, where the thickness of said
thin wall sections is selected to permit said plurality of screw
threads to ratchet over the threads of a threaded stud having said
particular thread pitch when said fastener is pushed inwardly
thereon.
6. A wing-nut fastener as defined in claim 5, wherein the flank of
each of said thread surfaces of said thin wall sections which faces
towards said base has a convex curvature to ease the ratcheting of
said plurality of screw threads over the threads of a threaded stud
having said particular thread pitch when said fastener is pushed
inwardly thereon.
7. A wing-nut fastener as defined in claim 5, wherein the axial
distance between said cylindrical opening and said central aperture
is less than the length of a particular threaded stud such that the
free end on said particular threaded stud will be contained in said
cylindrical opening of said head portion when said fastener is
fully seated onto said particular threaded stud to thereby rigidly
support said fastener thereon.
8. A wing-nut fastener as defined in claim 5, wherein each of said
leg portions taper inwardly from said base towards said head
portion in a perpendicular direction relative to the longitudinal
dimension of said head portion to thereby reinforce the support of
said head portion and said pair of thread forming members.
Description
BACKGROUND OF THE INVENTION
Push-on fasteners have a wide variety of uses in assembly line
operations where the speed of securing the fastener in place is
very important. Many prior art push-on fasteners provide very
little holding power because they do not have a threaded engagement
relationship between the fastener and the stud on which it is
mounted. This invention is an improvement over such prior art
devices in that it provides the combination of installing the
fastener on a threaded stud by an inward push and a threaded
engagement being established through the ratcheting action of the
thread surfaces of the fastener over the stud's threads.
One of the objects of designing a push-on fastener is to provide an
inexpensive method of manufacture. This invention utilizes a design
that can be economically fabricated on injection mold
equipment.
As will be more apparent from the following description, the
plastic fastener embodying the principles of this invention may be
installed rapidly and has a wing-nut configuration for easy removal
by unscrewing. The fastener is thereafter reusable and can be
molded to conform to other thread types.
SUMMARY OF THE INVENTION
The one-piece plastic wing-nut fastener embodying the principles of
this invention is designed to be pushed onto a threaded stud and be
held in a threaded engagement by virtue of the ratcheting action
provided by a pair of opposing arcuate thin wall sections having
internal thread surfaces that together form a plurality of screw
threads. The pair of arcuate thin wall sections are supported
between a head portion and a base through the use of a pair of
spaced leg portions which interconnect the base and head portion
and are in parallel with the thin wall arcuate sections. The
U-shaped configuration provided by the pair of legs and head
portions present a wing nut configuration that facilitates the
unscrewing of the fastener from the threaded stud.
DESCRIPTION OF DRAWING
For a better understanding of this invention, reference may be made
to the accompanying drawing, in which:
FIG. 1 is a front elevational view of the preferred embodiment of
this invention illustrated as it is being pushed onto an upstanding
threaded stud;
FIG. 2 is a cross-sectional view of FIG. 1 taken along the lines
2--2;
FIG. 3 is a top plan view of the preferred embodiment illustrated
in FIG. 1;
FIG. 4 is an enlarged fractional sectional view taken along the
lines 4--4 of FIG. 3; and
FIG. 5 is a side plan view of the preferred embodiment of FIG. 1
taken from the right side thereof.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the drawing, there is shown a one-piece plastic
fastener having a wing-nut configuration and generally designated
by the reference numeral 10. The fastener 10 has a circular disc
base 12 with a central aperture 14 formed through its center
portion.
Integrally formed with the base 12 is a U-shaped support 16 which
consists of a head portion 18 and a pair of leg portions 20 and 22.
The pair of leg portions 20 and 22 are integrally formed with the
circular base 12 in a normal relation.
The head portion 18 has a central collar section 24 and a pair of
arcuate wing sections 26 and 28 which are integrally connected to
the leg portions 20 and 22, respectively. It is noted that the wing
sections 26 and 28 are large enough to provide easy gripping and
turning by the user.
The collar section 24 has a central opening 30 in axial alignment
with the central aperture 14 of base 12 and is of substantially the
same diameter as that of aperture 14.
As illustrated in FIG. 5, the leg portion 20 of U-shaped support 16
has side edges 34, 35 converging inwardly between the circular base
12 and the head portion 18 in a perpendicular direction to the head
portion 18. Leg portion 22 has an identical side configuration. The
purpose of the truncated triangular configuration of the leg
portions 20 and 22 is to provide a very rigid mounting of the
U-shaped support 16 on the base 12.
There is integrally formed between and parallel to the leg portions
20, 22 a pair of opposing thread forming members 38 and 40. The
thread forming members 38, 40 are identical in construction and are
formed of a thin wall section 42 and 44, respectively. The thin
wall sections 42 and 44 are disposed to be axially aligned between
the central aperture 14 in base 12 and the central opening 30 in
collar section 24. The thin wall sections 42 and 44 have a
plurality of threaded surfaces 46 and 48, respectively, formed on
the interior wall surfaces, which together form a thread that
provides a substantial amount of thread engagement as will be
explained hereinafter. It will be appreciated by those skilled in
the art that this thread configuration permits a side action tool
to form the threads during the molding operation and to be
retracted without the need of any rotary motion.
To ease in the insertion of the fastener 10 on a threaded stud,
each flank 50 and 52 of the thread surfaces 46 and 48,
respectively, has a convex surface facing the base 12 as depicted
in FIG. 4. It will be appreciated from referring to FIG. 4, that
the convex flanks 50 and 52 readily ride over the threads of the
threaded stud as the fastener 10 is pushed onto the stud.
In the use of this invention, the fastener 10 is readily gripped by
the wing sections 26 and 28 and placed onto a threaded stud such as
stud 60 illustrated in FIG. 1. The enlarged diameter of central
aperture 14 slips over stud 60 and the convex flanks 50 ride over
the threads of stud 60 as the fastener 10 is pushed downwardly. As
the threads 46 and 48 ride over the stud 60 the thin wall sections
42 and 44 flex radially outwardly to provide a ratcheting action of
the threads 46 and 48 over the threads 62 of stud 60.
It is preferred that the length between the collar section 24 of
head portion 18 and the base 12 is shorter than the length of the
threaded stud 60 so that the upper end of the stud 60 will be
seated within the central opening 30 of collar section 24 when the
fastener is fully installed on the stud. With the upper end of the
stud 60 being retained in the collar section 24, any lateral forces
directed to the head of the fastener 10 will prevent it from
wobbling.
Once the fastener 10 is pushed onto the threaded stud 60, it will
be appreciated that the thread surfaces 46 and 48 of the thin wall
section 42 and 44 will be held in threaded engagement with the
thread 62 of the stud 60. Thereafter, to remove the fastener 10, it
will be necessary to unscrew the fastener by rotating the head
section 18 counterclockwise.
* * * * *